Changing battery in the key?

[BALIKBAYAN]

My keys to the car starts to be very bad. The key I use all the time has lost the lock button, but I can still use it if I put my fingernail in the hole of the button and press the tiny button inside of the key. I tried my spare key, wich I never use, but bring with me when I go on longer trips (holidays etc...), has stopped working. I guess it needs a new Battery. I read in the workshop manual about changing the Battery in the transmitter inside of the key. It looks like it is a very simple job to do, but I could not find wich kind of Battery I need to buy. It was only mentioned lithium battery. Please see the attached file. What kind of battery do I need to buy?

I plan to change battery next week as I will be away with the car the week after that and I want to bring two working keys with me.

 

m_73_0017.pdf

[Patonski]

Its an easy job just open one key and you'll see the Battery type on the Battery , I did both my Yaris keys for a 2008 model , easy job.

[gazza1286]

My 2008 has the standard 3-button key. I fitted a CR2016. 

There's a number of YouTube videos which describes the process. However I couldn't find a one which was specific for that particular key - but the principal is the same.  A watchmaker's cross head driver is required. Make sure you apply firm downward pressure to avoid rounding the screw. 

[m456an]

Or you could take it to a locksmith, and tell them to try to fix the button also. Though I am not good with these things, every watch I have tried to replace Battery I have messed up.

[Konrad C]

With my old and current Avensis, I alternated the use of the keys to minimise wear on the buttons. I sold my old Avensis with the keys in good condition and the complete set. I have seen Avensis keys in shocking state, and these cars are younger than old Avensis. Some owners do not take care, until a key stops working or lost, leaving the car unable to function properly. 

Toyota keys are not the worse though. Some cars have a special master key, which if lost makes the car nearly useless/worthless. I always check the car has all keys that come with it before purchase!
As for Battery change, I had an issue with the old Mk1 car when a key went out of sync. It is covered in the owner's manual. The current car does not have this system, but hopefully does not need it.

[BALIKBAYAN]

Thanx for the very good answer Gazza 1286. You were the only one who actually answered my question.

[BALIKBAYAN]

The most difficult in changing the Battery in the keys was to remember to buy a Battery and to find it in the shop. I changed the Battery in both keys, the grey key without buttons doesn't have any battery. I guess they will last at least 5 or 6 years from now. I doubt the car will last that long though. I bought 2 Energizer CR2016 for less than £ 3.